An integrative functional genomic and gene expression approach revealed SORBS2 as a putative tumour suppressor gene involved in cervical carcinogenesis
CARCINOGENESIS
Authors: Backsch, Claudia; Rudolph, Bettina; Steinbach, Daniel; Scheungraber, Cornelia; Liesenfeld, Melanie; Haefner, Norman; Hildner, Markus; Habenicht, Andreas; Runnebaum, Ingo B.; Duerst, Matthias
Abstract
Human papillomavirus (HPV) types 16 and 18 are known to play a major role in cervical carcinogenesis. However, additional genetic alterations are required for the development and progression of cervical cancer. Our aim was to identify genes which are consistently down-regulated in cervical cancers (CxCa) and which are likely to contribute to malignant transformation. Microarray analyses of RNA from high-grade cervical precancers (CIN2/3) and CxCa were performed to screen for putative tumour suppressor genes (TSG) in predefined regions on chromosomes 4 and 10. Validation of the candidate genes was done by quantitative reverse transcription-polymerase chain reaction (qRT-PCR) in 16 normal cervical tissues, 14 CIN2/3 and 16 CxCa. The two most promising genes, SORBS2 and CALML5, were expressed ectopically in various cell lines in order to analyse their functional activity. Reconstitution of SORBS2 expression resulted in a significant reduction in cell proliferation, colony formation and anchorage-independent growth in CaSki, HPKII and HaCaT cells, whereby anchorage-independent growth could only be investigated for CaSki cells. SORBS2 had no effect on cell migration. In contrast, reconstitution of CALML5 expression did not influence the phenotype of all cell lines tested. None of the genes could induce senescence or apoptosis. Our results underline a possible role of SORBS2 as a TSG in cervical carcinogenesis.
Comparative transcriptome analysis of human conjunctiva between normal and conjunctivochalasis persons by RNA sequencing
EXPERIMENTAL EYE RESEARCH
Authors: Xiang, Minhong; Zhang, Wei; Wen, Hang; Mo, Lijuan; Zhao, Yanqing; Zhan, Yueping
Abstract
Conjunctivochalasis (CCH) is a common ocular disease, especially in aged people. However, the molecular mechanism of CCH on transcriptional level has been unclear. In this study, we characterized the transcriptional landscape of human conjunctiva and compared the transcriptome between normal persons (n = 10) and CCH patients (n = 11). Illumina RNA sequencing (RNA-seq) was performed to obtain transcriptional data, and these data were analyzed using various bioinformatics methods, including read mapping, the analysis of gene expression, gene ontology (GO) analysis and Kyoto Encyclopedia of Gene and Genomes (KEGG) metabolic pathway analysis. Additionally, expression patterns of 20 dysregupated genes were validated by qRT-PCR. RNA-seq result showed that clean ratios of 21 samples were more than 95% and more than 92% of all clean reads (32-41 million reads) were mapped to human genome sequence. There were 175 up-regulated genes and 582 down-regulated genes identified in CCH compared to normal persons. Among down-regulated genes in CCH, many genes were related with cell cycle and proliferation, such as BUB1, CCNB1, CCNB2 and CENPA, which might disturb cell growth and proliferation. In addition, several down-regulated genes were associated with keratinization and differentiation of epidermal cells, such as SPRR1A, SPRR1B, and CALML5. In over-expressed genes, CALML6 might play important roles on the development of CCH. The results of qRT-PCR confirmed the accuracy and credibility of RNA-Seq analysis. This study provided a lot of valuable information about pathogenic mechanism of CCH, which could be used to better study CCH in the future.